The present invention relates to a cycle-controlled electrical power converter having DC input, and also known as a switching power supply. The input of the converter is connected to a power supply and the converter includes switch means for interrupting conduction in order to supply a predetermined quantity of energy to its output during each fixed-duration cycle.
Known converters of this type exist in which the switch means are controlled as a function of a control parameter Vc which is a function of the error between an output parameter and a reference value for said output parameter. The control parameter may directly determine the conduction period, or else, for example, it may determine te maximum value of the current to be delivered to the load. Such converters necessarily require servocontrol as a function of their output voltage or current. If such servocontrol is not very effective, the converter allows disturbances present on the inlet power supply to pass through to the outlet load.